褐藻寡糖对樱桃谷鸭生长性能、免疫性能、血清抗氧化能力及肠道发育的影响OA

This study aimed to investigate the effects of dietary supplementation with Alginate Oligo-saccharides(AOS)on the growth performance,immune performance,serum antioxidant capacity,and in-testinal development of meat ducks.A total of 480 healthy one-day-old Cherry Valley ducks(half male and half female)were randomly assigned to four groups,each with six replicates of 20 ducks.The control group received a basal diet without AOS,while the experimental groups were supplemented with 100 mg/kg,200 mg/kg,and 400 mg/kg AOS in the basal diet.The trial lasted for 42 days.At the end of the ex-periment,body weight was measured to calculate growth performance parameters.Immune indices and se-rum antioxidant markers were measured,and tissue samples from duodenal,jejunal,and ileal were col-lected to prepare paraffin sections.The results showed that compared with the control group,supplemen-tation with 200 mg/kg and 400 mg/kg AOS significantly reduced the feed-to-gain ratio(F/G)during both the 22-42 d period and the entire 1-42 d period,while 200 mg/kg AOS significantly increased the average daily gain(ADG)during the full 1-42 d phase(P＜0.05).Ducks in the 200 mg/kg and 400 mg/kg groups exhibited significantly higher thymus indices,increased serum levels of IgA and IgG,and elevated anti-in-flammatory cytokines(IL-10 and TGF-β),along with significantly reduced levels of the pro-inflammatory cytokine IL-1β at 42 d(P＜0.05).The addition of 200 mg/kg AOS significantly increased the serum super-oxide dismutase(SOD)activity,while 100 mg/kg,200 mg/kg,and 400 mg/kg AOS significantly reduced the serum malondialdehyde(MDA)levels at day 42(P＜0.05).Furthermore,200 mg/kg and 400 mg/kg groups significantly increased the weights of duodenum and jejunum,as well as the villus height in the je-junum and ileum at day 42.Additionally,all AOS-supplemented groups had significantly decreased crypt depth in the ileum at day 42(P＜0.05).In conclusion,dietary supplementation with 200 mg/kg AOS ef-fectively enhances growth performance,immune performance,blood antioxidant capacity,and intestinal development in Cherry Valley ducks,suggesting its potential as a functional feed additive in duck produc-tion.